Raipur: In one of the deadliest Naxal attacks in Chhattisgarh, the founder of the anti-Naxal movement, Salwa Judum, Mahendra Karma was killed on Saturday evening in Jagdalpur district. Apart from Karma, a Congress MLA was killed, the state Congress president was kidnapped and another party leader was seriously hurt in the attack.

The attack on the Congress convoy occurred during the Opposition party's Parivartan Yatra in Sukma district, police said.

According to Chhattisgarh ADG, Intelligence, Mukesh Gupta, Karma and a party MLA had been killed while state party chief Nand Kumar Patel was missing and senior leader Vidya Charan Shukla had been grievously injured, sustaining three bullet injuries.

Nand Kumar Patel, PCC chief, and his son Dinesh were abducted by Maoists in a dense forest in the district.

Prime Minister Manmohan Singh has offered additional forces to the state for help. The Home Ministry, sources said, was rushing forces to the state to tackle the crisis. Congress president Sonia Gandhi met the PM to discuss the issue while MoS Home RPN Singh said he would visit the state on Sunday.

The Chhattisgarh Congress, on the other hand, has called for a statewide bandh on Sunday in protest.

What has baffled experts is that Karma was killed despite having 'Z' category security. MHA confirmed that at least 21 people have died in the attack. "Close to 30 people are injured. The casualty figure could go up," MHA sources added.

The MHA sources also said that the Congress convoy was targeted in the landmine blast which was followed by continuous firing. A MHA delegation will be travelling to Chhattisgarh on Sunday morning.

The ultras reportedly opened fire on the 'Yatra' when it reached near forested Geedam Ghati area on way to Jagdalpur, injuring local worker Gopi Vadhwani, the police said.

Chhattisgarh Congress media cell president Shailesh Trivedi, however, said it was matter of investigation whether Naxals were involved in the attack. He alleged that ruling BJP government did not provide adequate security to the Congress' Yatra despite opposition from Naxals.

"Naxals have opposed both BJP's Vikas Yatra and Congress' Parivartan Yatra. However, the state government provided security only to BJP's Yatra and not to the one organised by Congress. Had it been provided security, today's incident would not have happened," he said.

Trivedi said he was trying to contact the party leaders who were part of the Yatra but was unable to do so as the incident occurred in forested area. Congress had launched Parivartan Yatra on April 12 in the state where Assembly elections are due by year end.